DU-III — Blast and Gastight Shelter Door (4.4 bar)

6 days ago

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Introduction

The DU-III Blast & Gastight Door is a protective shelter door designed to withstand blast pressure exceeding 440 kPa (4.4 bar) and provide gas tightness. According to the product information published by Atmas Group, DU-III doors are designed for civil defence shelters and other protected facilities. They are available in single-leaf and double-leaf configurations. Atmas Group

The door leaf is constructed from reinforced beams with steel cover panels. The design incorporates a multipoint locking mechanism and a special seal for gas tightness. Optional armour plates can be added for splinter and ballistic protection. Atmas Group

DU-III doors are intended for both new construction and retrofit projects, making them suitable for consideration in different shelter construction and renovation scenarios. Atmas Group

Official product page: DU-III — Blast & Gastight Shelter Door

Blast Resistance

The DU-III door has a specified blast rating of more than 440 kPa (4.4 bar). This rating is stated in the product documentation for applications in civil defence shelters. Atmas Group

The door is designed to protect the internal space against blast-wave pressure. According to the manufacturer, the DU-III series is intended for shelter installations where blast resistance and gas tightness are required.

The specified blast rating is a key parameter when evaluating the door for a particular project. The suitability of a complete installation depends on the design requirements of the protected facility and the selected door configuration.

Gastight Construction

The DU-III is specified as a gastight door and is equipped with a special seal for gas tightness. The sealing arrangement is designed to help prevent harmful gases from entering the protected space. Atmas Group

This feature is particularly relevant to shelter applications in which the door forms part of the protected perimeter.

Gastightness is one of the main characteristics of the DU-III design, alongside its specified blast resistance and multipoint locking mechanism.

Door Leaf Construction

The DU-III door leaf is made from reinforced beams with steel panels. The manufacturer also specifies the option of adding armour plates for additional splinter or ballistic protection. Atmas Group

The main construction features include:

Reinforced-beam door leaf.
Steel cover panels.
Optional armour plates for splinter or ballistic protection.
Special seal for gas tightness.
Anticorrosion primer.

These characteristics are based on the published product specifications. Additional fire-resistant materials may also be available according to the product description supplied for this article.

Multipoint Locking Mechanism

The DU-III uses a wheel-operated locking mechanism with multiple locking points. The locking system is designed to secure the door leaf and support its protective function against blast-wave pressure. Atmas Group

The multipoint arrangement is one of the defining mechanical features of the door.

The product description identifies a single wheel operating multiple locking points. This specification distinguishes the locking mechanism from a conventional single-point lock.

Available Sizes and Configurations

According to the supplied product specifications, the DU-III is available in the following sizes:

Parameter	Specification
Size option 1	800 × 1800 mm
Size option 2	900 × 2000 mm
Size option 3	1200 × 2000 mm
Door configuration	Single or double leaf
Installation options	Casting or retrofit
Orientation	Right- or left-hand configuration

The manufacturer’s technical catalogue also lists the 900 × 2000 mm and 1200 × 2000 mm configurations, with custom sizes available on request. Atmas Group

The required dimensions and configuration should be confirmed for the specific project before ordering.

Installation Options

The DU-III is designed for casting or retrofit installation, with right- and left-hand configurations specified in the product information. Atmas Group

These options allow the door to be considered for both new shelter construction and the renovation of existing facilities.

The appropriate installation method depends on the project design, the opening dimensions and the selected door configuration.

Main Technical Specifications

Parameter	DU-III specification
Product type	Blast and gastight shelter door
Blast rating	>440 kPa (4.4 bar)
Gas tightness	Yes
Door leaf	Reinforced beams with steel panels
Optional protection	Armour plates for splinter / ballistic protection
Door configuration	Single or double leaf
Available sizes	800 × 1800 mm; 900 × 2000 mm; 1200 × 2000 mm
Installation	Casting / retrofit
Orientation	Right / left
Locking mechanism	One wheel with multiple locking points
Seal	Special seal for gas tightness
Surface protection	Anticorrosion primer

The specifications above are based on the product information provided and the manufacturer’s published technical materials. Atmas Group

Applications in Civil Defence Shelters

The DU-III is designed for civil defence shelters and protected facilities where blast resistance and gas tightness are required. The manufacturer also describes DU-series doors as suitable for new construction and retrofit applications. Atmas Group

Potential applications based on the published product description include:

Civil defence shelters.
Bunkers.
Protected facilities.
New shelter construction.
Renovation and retrofit projects.

Optional armour plates can be specified where additional splinter or ballistic protection is required, subject to the available configuration.

Conclusion

The DU-III Blast & Gastight Door combines a specified blast rating exceeding 440 kPa (4.4 bar), gas-tight sealing and a multipoint locking mechanism.

Its main characteristics include reinforced-beam construction with steel panels, optional armour plates, casting or retrofit installation, and single- or double-leaf configurations. The specified size options are 800 × 1800 mm, 900 × 2000 mm and 1200 × 2000 mm.

For complete product details and purchasing information, consult the official Shelter Shop product page and the manufacturer’s technical documentation.